The assessment summary has landed, you have lost, and something in it looks wrong. We don’t mean “we deserved better”, which is how most losses feel for a week. We mean wrong on paper: a criterion marked absent when the evidence sits on page 12 of your submission, a score that contradicts the published weightings. We have written before about getting real value from feedback and debriefs, and our view there was blunt: most procurement challenges are expensive, slow and rarely the right call.
Check which rules your tender is under
Two regimes are running side by side. The Procurement Act 2023 went live on 24 February 2025, and procurements started before that date continue under the relevant previous procurement legislation, which may be the Public Contracts Regulations 2015. A framework competition that opened in 2024 under PCR 2015 remains governed by those regulations, with different deadlines and different case law. Everything below describes the Act. If your tender began under the old rules, the shape is similar but the numbers are not, and you need advice on that regime specifically.
What a challenge actually is
In England and Wales, a challenge is a civil claim, issued in the High Court (in practice the Technology and Construction Court), arguing that the buyer broke the rules the Act imposes on it. Section 100 makes a contracting authority’s duty to comply enforceable by suppliers who have suffered loss, or are at risk of it, because of a breach. The remedies are what you would expect from a court: damages for what the breach cost you, orders correcting a decision before the contract is signed, and in limited cases an order setting aside a contract that has already been entered into.
What a challenge is not: an appeal. No court will re-mark your bid or substitute its own view of quality for the evaluator’s. The claim has to identify a breach of the rules, which is why a score you disagree with goes nowhere and a score that contradicts the buyer’s own published methodology is worth a close look. Our post on what the people scoring your bid are told to do sets out the discipline evaluators are meant to follow; a challenge lives in the gap between that discipline and what your assessment summary shows actually happened.
The clock decides more than the merits
The sequence is tighter than most bidders realise. After a competitive tendering procedure, and before the buyer can publish its contract award notice, section 50(3) requires it to send every bidder whose tender was assessed an assessment summary. Publication of the award notice then starts the standstill period: at least eight working days, under section 51(2), during which the buyer cannot sign the contract. Framework call-offs, dynamic market awards and light touch contracts sit outside the mandatory standstill under section 51(3), among other exclusions, which is worth knowing before you assume you have a window at all.
The eight days matter because of what issuing a claim inside them does. Commence proceedings during standstill, and notify the buyer that you have, and section 101 suspends the contract automatically: entry into the contract is suspended unless the suspension is lifted or modified, or proceedings are resolved. Miss the window and the suspension never arises. The buyer can sign the moment the standstill period expires, and once the contract exists your realistic remedy is damages rather than the contract. For most claims, the usual limit under section 106 is 30 days from when you first knew, or ought to have known, about the circumstances giving rise to the claim. A good-reason extension is capped at three months. Claims to set aside an entered contract have additional time rules.
So the real decision window is days, not weeks. Our advice in the debrief post stands: read your assessment summary against your submission the day it arrives, and if you find what looks like a demonstrable error, put it to the buyer in writing immediately, inside the standstill period. That letter costs you a day. Obtain procurement-law advice immediately if you may challenge. A complaint or request for review does not stop court time limits. Ask your adviser how correspondence affects the available routes. The letter creates a record, it puts the buyer on notice of the specific scores you have named, and buyers can correct genuine errors far more cheaply at that point than after a claim form is issued. Send it early in the window, because the decision on whether to issue proceedings has to be taken before the standstill ends, with or without a reply: wait for an answer that arrives on day nine and the suspension route has already gone.
What happens to the contract while you argue
If you did issue in time, the automatic suspension becomes the battlefield, because the buyer can apply to lift it, and usually has every reason to. Section 102 gives the court that power, and the test looks at the public interest in contracts being awarded lawfully and in avoiding delay to whatever the contract supplies, alongside the interests of the suppliers involved, including whether damages would be an adequate remedy for you.
The first reported decision on the new lifting test suggests it has teeth. In ParkingEye v Velindre University NHS Trust, decided in May 2026, the court refused to lift the suspension on a five-year car park management contract and said that several matters “would seem to provide a clear indication” that the new test is meant to be “substantively and not merely formally very different” from the old one. On 13 May 2026, twelve days later, the trust and the health board decided to withdraw the award and abandon the procurement (Find a Tender notice 2026/S 000-048278). Under the old test, authorities usually won these applications, and Cubic v Transport for London shows how: decided in January 2026 under the old PCR 2015 rules, it went the traditional way, suspension lifted on a revenue-collection contract valued in the judgment at around £800m for its seven-year initial term. One decision is not a trend, but if suspensions survive more often under the Act, a well-founded challenge issued inside standstill carries more weight with the buyer than it used to.
What it costs, honestly
The Technology and Construction Court’s annual report breaks its new claims down by type: in London alone, 66 of 450 new claims between October 2024 and September 2025 were procurement claims. A claim count does not tell you how often suppliers succeed; check the evidence behind any success-rate claim. What can be said: issuing a money claim carries a court fee of 5 per cent of the amount claimed of more than £10,000 and up to £200,000, capped at £10,000. Ask the court to set aside the decision as well and a further £663 fee applies for that non-money remedy (both figures checked 15 October 2026 against GOV.UK’s EX50 civil court fees guide). Either way the issue fee is the small end of the bill. Procurement litigation is specialist work, and it moves fast precisely because of the deadlines above. Lose, and the buyer’s costs are at stake as well as your own. For most SME-sized contracts the arithmetic is brutal, which is why the honest starting point is the debrief route, not the claim form.
The route most bidders never use
There is another route besides a letter and a lawyer: the Public Procurement Review Service, run from the Cabinet Office. It takes concerns from suppliers about a specific procurement run by a public body in its scope (central government and most English public bodies, but not devolved Welsh, Scottish or Northern Ireland authorities, and not NHS health care services procurement), about issues that arose within the last two years, and it can raise what you report with the authority concerned. You can ask the service to protect your identity, but confidentiality cannot be guaranteed where legal duties require disclosure. The service cannot award you damages and it is not a substitute for the court deadlines above, which keep running regardless. It will not act while the standstill period is running, and it steps back once you start legal action, which includes sending a pre-action letter, so it is a route for after the window or instead of court, not alongside it. What it can do is put weight behind exactly the kind of process failure an SME cannot economically litigate: scoring that ignores the published criteria, feedback that never arrives, payment terms ignored down a supply chain.
When a challenge is worth it
Mostly, no, and we say that as a business that makes its living helping SMEs win public work. The cases where a formal challenge deserves serious consideration have three things in common. The error is demonstrable on paper, from the assessment summary and the published evaluation criteria rather than a disagreement about judgement. The contract is large enough, or strategically important enough, to justify specialist legal costs with no guaranteed return. And you spotted it in time to act inside the standstill period, which is where almost all of your bargaining power sits.
Everything short of that, the standstill letter, the review service, and above all the discipline of reading every assessment summary properly, is cheap and underused. Reading assessment summaries is work we do with clients every week, and it sits inside our procurement advice service: checking the summary against the submission, separating a scoring error from a sore result, and deciding what is worth raising before the window shuts. If you have an award decision in front of you and something in it looks wrong, talk to us while the clock is still running.